Danielle Chiesi, a former consultant to hedge fund New Castle Funds and a key figure in the insider trading case involving Galleon Group founder Raj Rajaratnam, pleaded guilty today to three counts of conspiracy. She admitted receiving tips about a number of companies, including IBM and Sun Microsystems, and passing them on to her boss and others in the hedge fund industry. A former IBM executive pleaded guilty last year. Mr. Rajaratnam maintains his innocence and awaits trial next month.